Method and apparatus for separating onion from wheat



C. A. WHITTAKER.

METHOD AND APPARATUS FOR SEPARATING ONION FROM WHEAT.

APPLICATIONFILED FEB. 19, I921.

1,406,127. I Patented Feb. 7, 1922.

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p jam C. A. WHITTAKER.

METHOD AND APPARATUS FOR SEPARATING ONION FROM WHEAT.

APPLICATION FILED FEB. 19. I921.

1,406,127, Patented Feb. 7, 1922.

2 SHEETS- SHEET 2- Inventor.- Cyrus A! W/wJZta/(w UNlTED STATES CYRUS A. WHITTAKER, OF FREEBURG, ILLINOIS.

METHOD AND APPARATUS FOR SEPARATING- ONION FROM WHEAT.v

Application filed February 19, 1921.

To all whom it may concern:

Be it known that I, Grows A. Wm'rrAKER, a citizen of the United States, residing at Freeburg, in the county of St. Clair and State of Illinois, have invented new and useful Improvements in Methods and Apparatus for Separating Onion. from Wheat, of which the following is a specification.

This invention relates to the separation of wheat'from foreign substances mixed with the wheat such as onion, garlic or screenings. Heretofore it has been considered practically impossible. to eliminate onion and garlic from wheat, for the reasonthat thev specific gravity of the onion and garlic is substantially the same as the average specific gravity of the grains of wheat. In treating ungraded wheat with air currents in order to separate the onion and garlic, if the air currents were strong enough to remove the onion and garlic they would also carry away the lighter grains of wheat.

The general object of my invention is to provide a method and apparatus which will overcome this difficulty and will enable an efficient separation to be effected.

Further objects of the invention will appear hereinafter.

In the drawing;

Figure 1 is a longitudinal section through a machine embodying my apparatus for practicing my method; this view may be regarded as a vertical section taken on the line 11 of Figure 2; I Figure 2 is a cross section through the apparatus taken about on the line 22 of Figure 1; and r Figure 3 is a vertical section taken about on the line 33 of Figure-2.

The apparatus comprises a casing 1 of box form in the upper portion of which there is provided a rotary screen or separator 2 which is of conical or tapered form and mounted to rotate on the horizontal shaft 3. This separator may be rotated by a belt running over belt pulley l. The wheat is fed into the small end'of the conical separator through a suitable chute 5 and as the separator rotates, this wheat gravitates toward the large end and the tailings pass through a chute 6 to the outside of the cas ing. The separator is in the form of a conical shell of sheet metal and is provided with perforations of different lengths. In the present instance these perforations are of three grades corresponding to the small Specification of Letters Patent.

Patented Feb. 7, 1922.

Serial No. 446,289.

end 7, the middle portion 8, and the large moves along the separator it is graded.

thereby and falls into anyone of the three hoppers 10, 11 and 12 which hoppers have a common inclined bottom 13 which guides the wheat toward the three feed rollers 14, 15 and 16 mounted upon a common shaft 17 which is continuously rotated when the machine is in operation. (lo-operating with each corresponding roller there is provided a feed door 18 (see Figure 2) which has a hinge support 19 at its upper edge. The lower edge of each of these doors rests lightly against its corresponding roller and its effeet is to cause the wheat to descend in a relatively thin stream from the roller. In this WayI grade the wheat into different grades and permit each grade to descend in a stream. According to my method I then subject each stream to treatment which will effect the separation of the onion, garlic and screenings. That is to .say, I permit the different grades of grain to fall through air spaces confined within chutes, and I withdraw air from the confined air spaces ata plurality of withdrawal points on the side thereof. The air is withdrawn through openings in the walls of the chutes. Oppositeto these openings or withdrawal points I admit'air to the confined air spaces or chutes and thereby develop transverse air currents passing through the grain streams. These air currents carry off the onion, garlic and screenings. The effect of air streams developed in this way is greatly superior to the efl'ectof air blasts'developed by pressure, for many reasons among which are the following By withdrawing the air at a point in the side of the chute and admitting air at a point opposite, an air current is. developed moving in a straight line between the two openings. If it were attempted to develop a transverse air current between two such openings merely by admitting an air blast at one of the openings the effect of the air blast would be to diffuse itself in the confined air space of the chute and blow the lighter particles in all directions, producing a confusion of air currents within the chutes, which would resemble in no way the efficient operation of air currents such as I employ, and which I regulate at their point of admission as well as at their point of exit from the chute. In order to accomplish this I oppositely inclined guide shelves 21 and 21, some of which extend fromthe forward wall 22 of the chuteand the others from the rear wall 23.-

On the rear wall 23 at each point where the streams descend from the lower edge .of one of the shelves 21 I provide a draft opening 24 and in the forward wall of the chute opposite this draft opening I provide another draft opening 25. The draft opening 24 is provided with a damper plate 26 which lies On the upper face of itsshelf 21 and these damper plates may be moved up or down so that their upper ends will more or less obstruct the opening 24. Adjacent to each opening 25 in the forward wall of the'chute I provide a damper plate, 27 which may be moved up or down so as to more or less obstruct the openings 25. Each chute 20 is a wheat chute, that is to say, it carries the wheat mixed with the foreign substances which are being eliminated from the stream. Back of each wheat chute I provide a secondary chute or onion chute 28 correspond- 7 ing to each wheat chute. The openings 24 communicate with these chutes and within each onion chute below the corresponding opening 24 two inclined guide boards 29 are provided which meet together to form a central ridge 30. The rear walls 31 of the onion chutes are provided with the draft openings 32*- which all communicate with a suction box 32 which extends the full length of the machine. (See Figure 3.) The onion, garlic and screenings which come through the openings 24 fall onto the guide boards29 and slide down it so as to find outlets through hanging trap doors 33 which hang against the vertical end walls 28 (see Figure 1) and .cover outlet openings 34 through these walls. As the onion and screenings are being discharged tl'irough these trap doors 33 their hinges -35 permit the doors to open slightly, but as soon as a discharge occurs they close up by gravity.

In the lower part of the apparatus I pro vide two gutters 36 and 37 3 the former of which receives the separated wheat from which onion, garlic and screenings have been eliminated. This gutter is provided with a conveyor screw 38 which may be continuously rotated to discharge the wheat at one end of the gutter. These gutters are separatedby a dividing ridge 39 the vertex of which is substantially in line with the rear wall 23 of the wheat chutes and hencethe onion and screenings coming down the onion chutes will pass into the'gutter 37. In this gutter a conveyor screw 40 is provided which say, they are narrowest in the zone 7, of

intermediate width in the zoneS and widest in the zone 9. This form of screen is very efiicient in effecting a grading of the wheat, for the reason, that the wheat varies more in the maximum diameter of theberry than in any other dimension and as the axes of the perforations extendlongitudinally with the axis of the separator they are in the best position to align with the natural position of the grains of wheat as the cone revolves; it will be evident that the wheat grains tend naturally to arrange themselves with their longitudinal axes extending in this direction.

The inlet and outlet openings for the air through the main chutes are disposed substantially at the same level with each other so that they operate to produce substantially horizontal transverse air currents passing through the descending'grain'.

It should be noted also that the feed rollers v14, 15 and 16 which correspond to the chutes, operate not only to feed the wheat, screenings, and onion from the drum down into the chutes, but also operate to substantially close the outlets from the hoppers 10, 11 and 12 and substantially exclude air from entering the chutes at these points] Hence, the admission of the grainat this point does not tend to break the partial vacuum produced and by means of which I induce the horizontal transverse air currents through the descending grain.

The perforations are kept clear by means of a brush 45 disposed above the revplving screen. 7 V

What I claim is:

1. The method of separating grain from onion, garlic and screenings, which consists in separating the wheat into different grades, permitting the different grades to descend in streams, developing a partial vacuum on one side of the descending streams and subj ecting the streams to substantially horizontal transverse air currents developed by the partial vacuum to remove the onion, garlic and screenings. s

2. The method of separating grain from onion, garlic and screenings which consists air currents successively through the different streams to remove the onion, garlic and screenings, and regulating the character of the air currents to correspond with the grade of wheat in the different streams.

3., The method of separating grain from onion, garlic and screenings which consists in separating the wheat into different grades, permitting the different grades to fall through confined air spaces, developing a partial vacuum at one side of the confined air spaces and thereby withdrawing air from the air spaces at outlet points on the side thereof, and admitting air to the confined air spaces opposite and about on a level with the outlet points, and thereby developing substantially horizontal transverse air currents passing through the grain streams to remove the onion, garlic and screenings therefrom.

4. The method of separating grain from onion, garlic and screenings which consists in separating the wheat into different grades, permitting the different grades to fall through confined air spaces, developing a partial vacuum at one side of the confined air spaces and thereby withdrawing air from the air spaces at outlet points on the side thereof, and admitting air to the confined air spaces opposite and about on a level with the outlet points, and thereby developing substantially horizontal transverse air currents passing through the grain streams to remove the onion, garlic and screenings therefrom, and regulating the admission and outlet openings for the air to control the character of the air current to correspond to the different grain streams.

5. In apparatus of the class described for separating onion and screenings from wheat, the combination of a rotary perforated. drum having zones with different sized perforations to separate the wheat into grades, a main chute corresponding to each grade, feed rollers corresponding to the chutes for feeding the grain into the chutes from the drum, and operating to substantially exclude the air, a secondary chute adjacent to each main chute, a suction box and means for developing a partial vacuum therein, said chutes having openings in the walls thereof for guiding induced air currents through the wheat streams and into the secondary chutes operating to carry off the onion and screenings from the wheat streams, means for collecting and removing the wheat as it accumulates near the bottom of the main chutes, and means for collecting and removing the onion and screenings accumulating below the secondary chutes.

6. In apparatus of the class described for separating onion and screenings from wheat, the combination of a rotary perforated drum having zones with different sized perforations to separate the wheat into grades, a hopper corresponding to each zone, a rotary feed roller at the bottom of each hopper, a main chute corresponding to each feed roller receiving wheat therefrom, for carrying a descending stream of wheat, a sec ondary chute corresponding to each main chute, means for directing the air currents through the main chutes transversely to the descending chutes, a conveyor below the main chutes for removing the wheat and a conveyor below the secondary chutes for removing the onion and screenings.

7 In apparatus of the class described, for separating onion and screenings from wheat, the combination of a rotary perforated drum having zones with different sized perforations to separate the wheat into grades, a hopper corresponding to each zone, a rotary feed roller at the bottom of each hopper, a main chute corresponding to each feed roller, receiving wheat therefrom, and for carrying a descending stream of wheat, a secondary chute corresposding to each main chute, means for directing air currents through the main chutes transversely to the descending streams, said secondary chutes having discharge openings for onion and screenings with inclined guide boards for directing the onion and screenings toward the same, trap doors opening outwardly for covering the discharge openings, means for removing the wheat from below the main chutes, and means for removing the onion and screenings from below the secondary chutes.

8. In apparatus of the class described for separating onion and screenings from wheat. the combination of a rotary perforated drum having zones with different sized perfora tions to separate the wheat into grades, :1- main chute corresponding to each rade and through which a stream of the gra ed wheat descends, a secondary chute adjacent to each main chute, a suction box and means for developing a partial vacuum therein, each main chute and its corresponding secondary chute having openings in the walls thereof for guiding induced air currents through the wheat streams, into the secondary chutes and thence to the suction box, said air currests operating to carry off the onion and screenings from the wheat streams, said secondary chutes having discharge openings and inclined guide boards for directingthe onion and screenings toward the same, trap doors covering the discharge openings, means for removing the wheat as it accumulates below the main chutes, and means for removing the onion and screenings accumulating below the secondary chutes.

In testimony whereof, I have hereunto set In hand.

y CYRUS A. WHITTAKER. 

